134 " BU. c. 1. forsytS major on the [Feb. 19, 



Before proceeding to a review, one by one, o£ the genera of 

 Primates, a few general remarks on the lacrymal region will be 

 necessary. 



The crista lacrymalis posterior oi Human anatomy is the vertical 

 crest dividing the lacrymal into an anterior portion, the sulcus 

 lacrymalis, and a posterior. The crista lacrymalis anterior is that 

 part of the frontal process of the maxillary which in Man forms 

 medially the lower orbital margin, in front of the sulcus lacrymalis. 

 We can best describe the two fundamental types which interest 

 us here, by stating that in Lemurs, as a rule, the crista lacrymalis 

 posterior rides on the lower orbital margin, of which therefore 

 it forms a portion (PL XI. fig. 4, text-figs. 27, 28, 31, 37) ; the 

 anterior part of the lacrjmal thus becoming the pars facialis, the 

 posterior part the pars orbitaUs. In Man and. Simiidse it is the 

 crista lacrymalis anterior which rides on the lower orbital margin, 

 descending posteriorly into the orbit, where it forms the antei'ior 

 part of the sulcus I,, and, jointly Avith the hamulus lacrymalis, 

 delimits the lacrymal fossa. As a result, we have the lacrymal 

 fossa outside the orbit in the first type, inside the orbit in the 

 second (PI. XI. figs. 7 & 8). 



PfiOSIMIiE. 

 Aclapis parisiensis. 



The only Tertiary Lemur of which the lacrymal fossa is known 

 to me is Aclapis parisiensis. Two skulls from the French Phos- 

 phorites, in the Geological Department, show this region well 



Text-fig. 30. 



Orbital region of Adapts ixtrisicnsis (Br. M. Geol. Dep. No. M 1345), about 



f nat. size. 



(Lettering as in text-fig. 26.) 



preserved, especially the younger one (text-fig. 30), which exhibits 

 beautifully all the sutures. 



